PotBS - Interview @ MMORPG.com

"Balance is our mechanic that determines how well your attacks will land on your opponents and how well you defend against your opponents' attacks," said Drew. The loss of balance therefore directly affects your defense. It will regenerate during combat and there are skills that give you balance back, as well as skills that attack your opponent's balance directly. A move that players can do to regain their balance is to simply stun their opponent, then step back for a second or two. Of course, others might decide they'd rather take advantage of a stunned opponent to inflict more damage.